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Finding the Fourth Proportional to 388.29, 581.85 and 285.09

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Solution

The fourth proportional to 388.29, 581.85 and 285.09 is: 427.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.29 : 581.85 = 285.09 : x
  2. Step 2: Convert to fraction form
    388.29/581.85 = 285.09/x
  3. Step 3: Cross multiply
    388.29x = 581.85 × 285.09
  4. Step 4: Simplify right side
    388.29x = 165,877.43
  5. Step 5: Solve for x
    x = 165,877.43/388.29
  6. Step 6: Final answer
    x = 427.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.